Internal combustion motor



S. P. CHRISTIE Filed March 2, 1955 2 Sheets-Sheet 1 ina/miur pril l2, E938` INTERNAL; COMBUSTION'MOTOR April 12, 1938 s1 P. CHRISTIE INTERNAL COMBUSTION MOTOR Filed March 2, 1935 2 SheetsSheet 2 Patented Apr. 12, 1938 PATEN'VE" OFFICE INTERNAL COMBUSTION MOTOR Stanley Percy Christie, London, England Application March 2, 1935, Serial No. 10,279 In Great Britain March 7, 1934 1 Claim.

My invention relates to those internal combustion motors of the known type which use a combustion chamber above a liquid piston oscillating in a play-pipe for pumping liquid or for compressing gas, and more particularly to those of such motors as operate on a two-stroke cycle, to which the combustible mixture is supplied at a pressure above that of the atmosphere, and in which the charge enters through an admission valve at the top of the combustion chamber, and the exhaust gases leave by an exhaust valve located at the bottom of the space occupied by the charge at atmospheric pressure, hereinafter called the charge space, and also in which the combustible charge is caused by suitable guides to follow the exhaust in a path which extends downwards from the admission valve nearly to the lowest level of the liquid surface and then rises upwards to the dome of the combustion chamber and finally turns downwards again towards the exhaust ports.

The object of my invention is to enable the whole of the charge in this tortuous path to be substantially at one pressure at any instant during its compression or expansion, and also to facilitate the simultaneous ignition of all parts of the charge.

Referring to the drawings which illustrate merely by way of example means suitable for 30 carrying out my invention:

Figure 1 is a vertical section through the combustion chamber of armotor embodying my invention.

Figure 2 is a section of an alternative means for operation.

Figure 3 is a section through the combustion chamber of a large unit employing several admission valves.

In Fig. l, numeral I denotes the combustion 40 chamber closed at the top by seats 2 of the admission valves 3. Exhaust valve 4 is located so as to be closed in the known manner by the liq.- uid column 5 when this rises to the height at which the charge volume remains above it. The 45 admission valves 3 are in an opening E in the dome of chamber I, and from the edges of this opening an inner wall 'I extends downwards nearly to the lowest level to which the liquid falls in oscillating. Below the level at which the ris- 50 ing liquid closes the exhaust valve 4, the wall 'I has louvered openings 8 adapted to enable the mixture to pass through wall 1 and also to direct it downwards. The inner wall 1 is surrounded by an outer wall 9 which extends from below the 55 lowest level to which the liquid surface falls, to

near, but short of, the dome of the combustion chamber, so that the two spaces elsewhere separated by it are always connected over the top of it. The path of the exhaust gases initially followed by the new charge is therefore down- 5 wards both before and after passing through the louvers 8, then upwards between the inner wall l' and the outer wall 9, and then over the top of wall 9, and between it and the wall of the combustion chamber downwards to the exhaust 10 valves, as indicated by the arrows.

According to my invention a balance port I0, located near the top of wall l, is adapted, when open, to establish equilibrium between the combustion spaces on the two sides of wall 'I during l5 the compression and explosion of the charge.

A balance valve II adapted to close this port ISB is arranged to open it at or near the beginning of the compression of the charge by the rising liquid, and to keep open until the pressure dur- 20 ing expansion has fallen to a desired limit. In Fig. l, the lever l2 causes balance valve II to be opened by the closing of exhaust Valve 4 when this is touched by the rising liquid and compression of the charge begins.

Simultaneous ignition on both sides of wall 1 is ensured by the use of an ignition chamber I5, for example in the form of a ring pipe fed with combustible mixture similar to that passing through admission valve 3, for which purpose an auxiliary admission valve I 1 is used and operated synchronously with valve 3, and a non-return valve i6 is interposed between valve II and chamber I5. On the contents of this chamber being ignited by sparking plug I8, flame is projected through a number of short bifurcated ports I9 into the combustion spaces on both sides of the inner wall 'I at the same instant.

The operations of one cycle of an upward and a downward stroke of the liquid column are as 40 follows:

The column having moved downwards under the action of an explosion and having come to rest, the exhaust valve 4 has been opened by springs 2l) and the balance Valve II has been shut. Combustible mixture enters under slight pressure through valve 3 and in passing through louvers 8 in a downward direction displaces first the lowest portions of the exhaust gases between walls I and 9, and then follows this exhaust upwards and over the top of wall 9 until, by the time the liquid level has risen to the exhaust valve 4 and shut this, practically all the exhaust has been replaced by new charge. The further rising of the liquid column compresses this charge equally on both sides of wall 1, as ensured by the opening of valve II; and, on ignition, flame is projected into the mixture on both sides of wall 'I at the same instant.

In a convenient form of construction the inner wall 'I and outer wall 9 take the form of concen tric tubes of which the outer may be attached to the wall of the combustion chamber I by radial ns or vanes 22 which guide the gases so as to lessen dilusion between the new charge and the exhaust products. In Fig. 3 illustrating part of the combustion chamber of a large unit a plurality of admission valves each with a tubu- L. lar wall such as 'I and a balance Valve such as II and bifurcated ignition ports such as I9 may be used, and may be surrounded by one tubular outer wall such as 9, and the annulus between this Wall 9 and that of the combustion chamber may itself be divided into segments by varies 22. In Figure 3 vanes 2| divide the space within tube 9 into four parts.

In Figure 2, as an alternative mode of opening balance valve Il, it is shown connected through lever I2, with piston I3, of which the right face is acted upon by the pressure in the combustion chamber and the left face is acted upon by spring I4, which is adjusted so that valve I I shall be open while the pressure remains above a suitable limit.

I claim:

In an internal combustion motor having a combustion chamber over a liquid column oscillating in a play-pipe and operating on a twostroke cycle, an exhaust valve located at the bottom of the charge space, an admission valve located at the top of the charge space, an inner wall surrounding the admission Valve and extending from the combustion chamber top to the level of the exhaust valve, a perforated extension of this wall nearly to the lowest level of the'liquid surface, and an outer wall between the inner wall and the exhaust valve extending from below the lowest level of the liquid surface to near they top of the combustion chamber, the use of a balance port inthe inner wall adapted to be closed by a balance valve only while the pressure in the combustion chamber is below a desired limit.

' S. P. CHRISTIE. 

